The Tragedy of the Commons (ToC) was proposed by Garrett Hardin (1968), where individuals act independently and rationally according to one’s own self-interest, resulting in the exploitation of common pool resources (CPRs) till the point of degradation and collapse.

According to this theory, access to the CPR is open to all. Individuals focus on short-term gains with the goal of maximising their profits from the CPR, without taking others into consideration. These individuals continue to deplete the shared resource despite knowing that continued depletion will not benefit them in the long-term because there is no incentive for them to stop using the CPR.

In the past, when the population was small, there were no negative consequences as consumption levels were below the carrying capacity of the CPR. However, the exponential growth of the population has resulted in an increase in demand for food, causing consumption levels of multiple CPRs to rise above their carrying capacity. Sustainability can only be attained when the use of the resources is below carrying capacity. According to Hardin, this is known as the “population problem”.